You can promote a stereotype to metaclass status by selecting the Use as Metaclass check box in the stereotype property page. This can be useful when you need to:
Create new kinds of objects that share much of the behavior of an existing object type, such as business transactions and binary collaborations in a BPM for ebXML.
Have objects with identical names but different stereotypes in the same namespace (a metaclass stereotype creates a sub-namespace in the current metaclass).
Stereotypes defined on sub-objects (such as table columns or entity attributes), cannot be turned into metaclass stereotypes.
The new metaclass stereotype behaves like a standard PowerDesigner metaclass, and has:
A separate list in the Model menu - the parent metaclass list will not display objects with the metaclass stereotype. These objects will be displayed in a separate list, under the parent metaclass list. Objects created in the new list bear the new metaclass stereotype by default. If you change the stereotype, the object will be removed from the list the next time it is opened.
Its own Browser folder and command in the New contextual menu.
Property sheet titles based on the metaclass stereotype.